I might start saving for a dedicated folding build as a side project of mine. I want to make sure I get the most bang for the buck with one PC, so I assume I would do a 4 video card setup.

Just to make sure, is it possible to have 4 GPU's on one motherboard fold efficiently? Will I need a quad core CPU to handle all the processing or will a dual core CPU be ok?

In terms of power, how big of a power supply would I need? Is there any type of calculator where I can determine what power supply will be good enough for a 4 video card setup that will just be folding? I'm assuming that I would get 4 8800gt's.

How many amps would the PC be drawing? Would it be anywhere near tripping the circuit breaker when connected to a standard power strip? Is there a standard tripping point? (In case I add another older PC's to the farm)

I might start saving for a dedicated folding build as a side project of mine. I want to make sure I get the most bang for the buck with one PC, so I assume I would do a 4 video card setup.

Just to make sure, is it possible to have 4 GPU's on one motherboard fold efficiently? Will I need a quad core CPU to handle all the processing or will a dual core CPU be ok?

In terms of power, how big of a power supply would I need? Is there any type of calculator where I can determine what power supply will be good enough for a 4 video card setup that will just be folding? I'm assuming that I would get 4 8800gt's.

How many amps would the PC be drawing? Would it be anywhere near tripping the circuit breaker when connected to a standard power strip? Is there a standard tripping point? (In case I add another older PC's to the farm)

I'm sure someone will chip in with more solid answers, but here is a few that I can put in:4 GPUs on one motherboard - currently works fine, even for slots where the PCIe is running at 4x won't have a big impact. Consider however using GX2 cards (e.g. 9800GX2 is under $300). Can then use a cheaper motherboard and easier to manage.

With Nvidia cards, doesn't need much CPU power. A E5200 will currently easily handle all 4 cads, and most likely have one core free.

Power use, depends on what cards planning to get. Looks like a bit over 600 watts with 2 GX2s. But folding doesn't use as much as max GPU burn, so a great 750 watt PSU probably can handle it... barely http://www.techreport.com/articles.x/15293/10

Check powerbar - probably 13Amp max load. So would easily handle to 5 or 6 amps for this system

Themattman, I'm happy to report to you that folding with four video cards in one machine is entirely possible.. just take a look right below. This setup consists of 3 96000GSO cards and 1 8800GS card attached to a MSI K9A2 Platinum, and with a 8450 cpu. It's running Vista 64-bit, so the load on the cpu isn't as heavy, around 30% on two cores, as on XP. There is one caveat to successfully running this setup however, and that is Vista requires that a monitor be attached to each card and also the desktop to be 'extended', though there is a workaround to the monitor issue if you don't have the luxury of having multiple monitors to attach to this beast.

You'll notice that I have an Antec True Power 1000, which I admit is total overkill for this setup, being that the it only pulls about 370 watts (yes, the 9600GSO's and 8800GS are quite modest in power consumption).This number would probably go up to 500 watts if I install a SMP client on here, but that's another project for another day as I plan to overclock the 8450 first. Anyhow, below is the finished product:

Now the workaround for Vista extend desktop issue.. take a look at the picture below and you'll notice that there some are funny looking video adapters attached to the video cards. No, a dog (or a really mean gerbil) didn't come up and chew the heck out of my video cables.. these are actually homemade VGA dummy adapters to trick Vista into thinking that a monitor is attached to each of those connectors. I ran into the desktop issue when I worked on piecing this setup together and needed an economical solution.. thus my research lead me to this site. Now be warned that if you're squeamish and gets light-headed at the thought of working with a soldering iron, then read no further... go play with your Lego set or something. However, if hot iron doesn't faze you, then read on.

First you'll need to run to your local Radio Shack and grab the following items, if you don't already have them:

1) A soldering iron (obviously). Radio Shack should carry soldering sets for as low as $8.

2) DVI/VGA adapters. I have a bag full of these laying around, as I'm sure many people as well. If not, they can be easily found at your local electronics store.

3) Resistors. Now this site specifies 75 ohms resistors but my local Radio Shack stores didn't carry them, so I ended up getting 100 ohms, 1/4 watt resistors instead, which should be $1 for a pack of 5. See picture below. Please not that you'll need three resistors for each connector that you make, so plan accordingly.

4) D-sub 15-pin male connector. $2 at RD.

Once you have all the parts, the soldering fun begins! Just look at the pin-outs on the page that I had linked up top and start soldering. Now let me give you a tip on soldering these things together to save you a deal of frustration. When soldering the resistor to the pin, don't try to put the iron and the solder together with the resistor, instead, put the solder on top of the iron to let the solder melt onto the tip of the iron. With the solder now on the tip of the iron, move the iron tip to the point where you want to solder the resistor to the pin, and at this junction, the melted solder should just slide over to the joint and solidify. If this venture is successful, you should get something that looks like this... hopefully a little prettier than this as my soldering skill is.. well, a little rusty.

Here's the connector attached to the adapter.

One last advice, and that is after you connect the jerry-rigged adapter to the video card, you must reboot the computer before Vista can sense the attached adapter. Hope this helps!

David, the 9600GSO's are getting around 3700ppd while the 8800GS is getting around 4400ppd. Keep in mind that the 9600s' cores are all running at 550MHz while the 8800's core is at 680MHz. I'll try to overclock the 9600's to get their ppd closer to 4000. One thing I'd learned from this project is that when you're setting up a mult-gpu setup, you need to have cards with similar number of stream processors, otherwise the performance will be impacted drastically. For example, I used to have the 8800GS sitting in a system with an 8800GT (112 SP's) and the ppd for the 8800GS (96 SP's) was 3000, however, when I moved it to this setup with the 9600GSO's (96 SP's), the 8800GS' ppd when up to 4400.

flybywire wrote:David, the 9600GSO's are getting around 3700ppd while the 8800GS is getting around 4400ppd. Keep in mind that the 9600s' cores are all running at 550MHz while the 8800's core is at 680MHz. I'll try to overclock the 9600's to get their ppd closer to 4000. One thing I'd learned from this project is that when you're setting up a mult-gpu setup, you need to have cards with similar number of stream processors, otherwise the performance will be impacted drastically. For example, I used to have the 8800GS sitting in a system with an 8800GT (112 SP's) and the ppd for the 8800GS (96 SP's) was 3000, however, when I moved it to this setup with the 9600GSO's (96 SP's), the 8800GS' ppd when up to 4400.

Could it be just the WU mix that you are getting?

The Model M is not for the faint of heart. You either like them or hate them.

themattman wrote:Thanks for the post flybywire. With my mediocre soldering skills I think I could pull that off.

I have none, so you are better than me already.

themattman wrote:For the most PPD, would it be better to run Linux, XP, Vista, or Linux through XP/Vista? Are linux drivers usually up-to-date?

There is no Linux GPU client yet AFAIK. So your host system will have to be XP or Vista (probably Vista since the GPU2 client CPU utilization is less). Should you decide to run a CPU client in addition to the GPU clients, then you have a choice of WinSingleCore, WinSMP, or LinuxSMP via virtualization.

themattman wrote:Trying to cut costs but not quality, would a 600 watt power supply be sufficient for the PC's use or should I play it safe and go with a 750W power supply?

I would think a 600 is good enough. But those Corsair 750TX's are quite cheap.

themattman wrote:Would it be better to do a 4 card setup or get two 9800GX2's? Which would give the most PPD after some light overclocking?

David reported the 2nd GPU on this GX2 not doing the same ppd as the 1st, so may be 4 single-GPU cards would be better? Not sure about this one. People in the know should chime in on this.

themattman wrote:As a sidenote, I am looking around for a cool and quiet case. The Antec P182 looks like a quality choice.

P182 is not exactly cost-effective (cheap), but it is quiet. If the box is folding only I would go as cheap as possible.

The Model M is not for the faint of heart. You either like them or hate them.

flybywire wrote:David, the 9600GSO's are getting around 3700ppd while the 8800GS is getting around 4400ppd. Keep in mind that the 9600s' cores are all running at 550MHz while the 8800's core is at 680MHz. I'll try to overclock the 9600's to get their ppd closer to 4000. One thing I'd learned from this project is that when you're setting up a mult-gpu setup, you need to have cards with similar number of stream processors, otherwise the performance will be impacted drastically. For example, I used to have the 8800GS sitting in a system with an 8800GT (112 SP's) and the ppd for the 8800GS (96 SP's) was 3000, however, when I moved it to this setup with the 9600GSO's (96 SP's), the 8800GS' ppd when up to 4400.

Could it be just the WU mix that you are getting?

I'm positive it's not just the wu mix as I had the 8800GT + 8800GS setup running for over a month. The GS could not get any higher than 3000ppd with 480-point units and it would go down to around 1800ppd with the 430-point units.

As FF had stated, Vista would be your best bet to minimize load on the cpu.

As for the GX2, I recall David and JPinto having issues with those cards not producing at their optimum level, which is why I went with four separate cards.

I also agree with FF that the P182 case isn't a cost-effective choice for what you're proposing to do. In addition, I have doubts about its ability to circulate enough air to cool four video cards. I'm currently using an Antec Three Hundred case for my setup and I think it fits my needs pretty well, though not perfectly. It's a clean, no-frills case that can cool my setup well.. being that it has two 120mm front intake fans, 1 120mm rear outtake fan, 1 140mm top outtake fan, and best of all (I think) is the 120mm side intake fan to help cool the video cards. It's also relatively inexpensive, with Newegg selling it for $60, but if you have a local Microcenter to shop at, you can pick the case up for $40. On the negative side, the ps being located on the bottom of the case doesn't afford much room between the ps and the mb, which is why I had to place a single slot card on the last pci-e slot. Another minor gripe is that the top fan grill juts out, which prevents me from stacking another case on top of it.. but then again, that would impede the warm air that's exiting the case.

Thanks for all of your help. Now I have a good idea where I stand and how much I need to save. I think the best thing to do right now is wait and see how nehalem and the new motherboards measure up. Maybe by then we will even see some new graphics cards out and about

I can't recommend the 9800GX2 as a card for folding alone. You're better off with two 8800 or better cards. Now, if you want to game with the rig the 9800GX2 may be the way to go cause you get to SLI the GPUs, which you can't do on a nice intel mobo if you have two cards.

Otherwise, the 9800GX2 is kind of a PITA cause my second GPU puts out half the PPD of the first. I get anywhere from 7000PPD to 9000PPD on it depending on the WU and phase of the moon.

I think the 8800GS or 9600GSO is the best bang for the buck folding card. Actually, I think FBW pretty much nailed it perfectly with his rig in the best bang for the buck folding rig... Well, the PSU is overkill, and maybe he could have gotten away with a dual core, but otherwise, very well executed his rig is I must say.

I just play an hour of Crysis at 1920x1200 in Very High settings, so the 9800GX2 still has its usefulness (ppd may be down a tad today ) I have it OC'd to 720MHZ and it is a real screamer. I pulled out a sniper rifle and aimed it at a bad guy... it seemed photo-realistic... oh and this was in DX10 to boot.

If you're not folding with your idle computer time you're not part of the solution.

I haven't written off the 9800GX2 yet. I've got a PC with a single 9800GX2 and the 2 GPU's are doing 10500PPD day in and day out PLUS the SMP client points.

I think I might have a power supply problem with the PC that has both a 9800GX2 and 8800GTS in it that may be affecting the 9800GX2. A Seasonic 500W sounds like it's on it's way out. There is a lot of heat in these cases, so it will tax the PS thermally probably as much as power-wise. I'm erring on the side of overpowering, rather than underpowering these GPU's.

As a note, I'm finding a lot of high frequency screaching from the Nvidia GPU's. I had a high acclaimed PCPower&Cooling 750Watt supply that made a 9800GX2 screach to the point it drove myself and my wife crazy. I swapped the PS for a Zalman 850W, and the whining noise dropped dramatically.

I am still working towards two 9800GX2's in the same chassis in addition to 2 other 9800GT's for a total of 6 GPU's in one chassis. We'll see. I'll probably power it with a Zalman 1000W. I'll stick with WinXp even though it burns the CPU.

JPinTO wrote:As a note, I'm finding a lot of high frequency screaching from the Nvidia GPU's. I had a high acclaimed PCPower&Cooling 750Watt supply that made a 9800GX2 screach to the point it drove myself and my wife crazy. I swapped the PS for a Zalman 850W, and the whining noise dropped dramatically.

Interesting. I have the same PSU and the same screech. Do you know why the PSU would cause the card to screech?

If you're not folding with your idle computer time you're not part of the solution.

I replaced my failing Seasonic with the PCP&C 750W, and it didn't restore the missing shaders on one of the 9800GX2's GPU's. So, it wasn't a power issue.

The bad news, is that PCP&C 750W squeals like a piggy. May have to try an RMA. It's nasty.

I don't know anything about PSU's but there are many complaints about the whining, some say it's the GPU, and others the PSU. Definitely, this PCP&C 750 is a culprit for some high frequency noise. Something or another about capacitors. This is my first and last PCP&C. Could not be happier with the Zalman 850W. Silent!

I am having a weird issue now with my GPU clients on my 9800GX2. I tried adding the "-gpu0" flag after the target window of the properties section. When I run it I get a window showing me a list of flags. Basically, it's telling me I can't use the "-gpu0" flag. Has anyone seen this? How do you fix it?

Here is how I currently have it running.

If I add "-gpu0" in the target window I get this error when I try to run the GPU2 client:

If you're not folding with your idle computer time you're not part of the solution.

Yes indeed. Thanks! At appears I need that remedial reading class after all

Resolved, then?

Well I have successfully launched both GPu clients now with the "-gpu 0" and "-gpu 1" flags. The second GPU2 client is only at 1588PPD for the moment. The first one is at 4822PPD. Maybe it takes time for the average to recover?

If you're not folding with your idle computer time you're not part of the solution.

David, Are you running a second video card along with your 9800GX2 and if so, what motherboard are you using? If it's a mobo that switches the PCIe x16 slots to PCIe x8 when two physical cards are installed, you might be running out of bandwidth for your 9800GX2.

flybywire,Congrats on a sweet quad GPU setup and thanks for the how to do it! I like my Antec 300 almost as much as I like my Antec 900.

farmpuma wrote:David, Are you running a second video card along with your 9800GX2 and if so, what motherboard are you using? If it's a mobo that switches the PCIe x16 slots to PCIe x8 when two physical cards are installed, you might be running out of bandwidth for your 9800GX2.

flybywire,Congrats on a sweet quad GPU setup and thanks for the how to do it! I like my Antec 300 almost as much as I like my Antec 900.

I only have the one 9800GX2 in the rig and the other PCI-E slot is not utilized. Games seem to play pretty well, so I'm guessing the slot is at the full x16. It's an ASUS P5Q mobo with the P45 chipset. Q9450 CPU running at 3.5GHZ. 4GB of ram.

When I checked this morning the card was at 6000PPD total both clients added together. When I get home tonight I may tweak it a bit.

Right now SLI is disabled, but this is interesting. I've been able to get 8000PPD out of the card while is in SLI mode. Weird, huh?

If you're not folding with your idle computer time you're not part of the solution.

Did you try installing it in another PC to see if it is the 9800GX2 issue or a PC issue (OS/motherboard)? PITB for sure, but worth it for the 3500PPD that you are missing.

Alternately, I guess you could deinstall the card and drivers, and reinstall it to see if it will help.

- JP

I read the links. I've added the "-forcegpu" command for the 2nd client. I also reinstalled the drivers while the card was set to multiple monitors and the desktop was extended. When I left the house the 2nd client's PPD was at about 3000 PPD and was climbing. I'll give you guys another update when I get home as to how it's going.

I don't really want to install it in a new mobo. My 2nd rig is my wife's. I try to not fuss with it too much cause she doesn't want a computer with issues. I'm just lucky she let's me run two SMP clients in VM and a GPU2 client on her rig (It's a Q9450 at 3GHZ with an 8800GTSG92 @ 745MHZ)

If you're not folding with your idle computer time you're not part of the solution.

At least you're getting some GPU points. I have an 8800GT 512 and a 9600GSO 384 with zero PPD and no video from either on my Asus P5NSLI. I also have three other PCIe motherboards, but no more time to troubleshoot for at least a week.